SIMPLE APPROACH TO ELIMINATING DISTURBANCES IN ISOELECTRIC-FOCUSING CAUSED BY THE PRESENCE OF SALTS

It is well known that the resolution in isoelectric focusing (IEF) is impaired by the presence of salts, partly due to a decrease in the wid th of the pH gradient. In addition, the risk of precipitation increase s and the mobilization time for focused protein zones, an important st ep in IEF in capillary electrophoresis, is prolonged. To eliminate the se drawbacks, an on-tube desalting technique for IEF was developed, ba sed on an automatic substitution of the salts with an ampholyte soluti on in a short focusing step prior to the final analytical isoelectric focusing procedure.